#define  _CRT_SECURE_NO_WARNINGS
#include<iostream>
using namespace std;
#include"string.h"


void test01()
{
	string s1("hello");
	string s2;

	for (int i = 0; i < s1.size(); i++)
	{
		cout << s1[i] << " ";
	}
	cout << endl;
	for (int i = 0; i < s2.size(); i++)
	{
		cout << s2[i] << " ";
	}
	cout << endl;
	cout << s2.c_str() << endl;
}
